Stmicroelectronics ST-ONEMP Digital Controller Simplified high Energy efficiency dual port USB-PD adapter design

     The ST-ONEMP digital controller is based on the market-first ST-ONE architecture and integrates an Arm Cortex-M0+ microcontroller, a highly energy efficient non-complementary Active clamper flyback controller, and a USB-PD 3.1 interface in a single package. The current isolation between the primary and secondary side circuits of the ST-ONE architecture greatly simplifies the design and assembly of the USB-PD power adapter.

     Now, by adding power sharing support, the latest ST-ONEMP simplifies the design of dual charging ports with an additional output in addition to the USB-PD output, improving end-user charging flexibility and convenience.

     Inside the ST-ONEMP, the Cortex-M0+ MCU microcontroller is located on the secondary side of the charger, and 64KB of flash memory on the chip is used to store the custom USB-PD protocol and power conversion firmware. The microcontroller comes pre-loaded with USB-PD 3.1 PPS certified firmware, allowing developers to provide master package solutions for standard applications. The MCU controls the synchronous rectifier and flyback converter, and the microcontroller is optimized for the zero-voltage switch non-complementary active clamp topology, which is more energy efficient than the traditional quasi-resonant flyback transform topology at high power.

     ST-ONEMP is compatible with stmicroelectronics MasterGaN power technology. MasterGaN technology consists of stmicroelectronics integrated gate driver gallium nitride (GaN) broadband gap power transistors. Stmicroelectronics GaN technology offers a higher switching frequency than traditional silicon mosFets, enabling the adapter to deliver higher power density and high energy efficiency in line with the latest eco-design specifications.

     Stmicro developed the EVLONEMP 65W + 10W AC/DC adapter reference design with ST-ONEMP and MASTERGAN4. The adapter is comparable in weight and volume to a 20W single-port smartphone charger. Peak energy efficiency was 94 percent, 2 percent higher than comparable conventional dual-port adapters, and the PCB area was only a quarter of that of conventional adapters. As a result, Oems can downsize enclosures, save energy, use less plastic and offer more environmentally friendly products.